Development of Ni–Mo/Al<SUB>2</SUB>O<SUB>3</SUB> Catalyst for Reverse Water Gas Shift (RWGS) Reaction

Abstract

In the present study, Mo/Al2O3 catalyst was prepared using impregnation method. Then it was promoted with Ni ions to produce Ni-Mo/Al2O3 catalyst. The structures of the catalysts were studied using X-ray diffraction (XRD), Energy dispersive X-ray (EDAX), Brunauer-Emmett-Teller (BET), X-ray photoelectron spectroscopy (XPS), CO chemisorption, temperature programmed reduction of hydrogen (H2-TPR) and scanning electron microscope (SEM) techniques. Catalytic performances of the two catalysts were investigated in a fixed-bed reactor for RWGS reaction. The results indicated that addition of nickel promoter to Mo/Al2O3 catalyst enhances its activity. It is reasonable for the electron deficient state of the Ni species and existence of NiMoO4 phase to possess high activity in RWGS reaction. Stability test of Ni-Mo/Al2O3 catalyst was carried out in a fixed bed reactor and a high CO2 conversion for 60 h time on stream was demonstrated. This study introduces a new catalyst, Ni-Mo/Al2O3, with high activity and stability for RWGS reaction.

Potassium‐Promoted Molybdenum Carbide as a Highly Active and Selective Catalyst for CO2 Conversion to CO

“…At the higher temperature,t he 3wt% K-Mo 2 C/g-Al 2 O 3 resultsi n4 0.5 %c onversion and 98.2 %C Os electivity,w hich outperforms 2wt% K-Mo 2 C/g-Al 2 O 3 and the industrial ZnO/Al 2 O 3 and ZnO/Cr 2 O 3 catalysts. [16] Ac omparison of the catalysts used herein with other relevant catalysts is also included in Table 1a nd the Supporting Information to demonstrate the high selectivityo fK -Mo 2 C/ g-Al 2 O 3 .F urther reactor and spectroscopic studies are required [29] 17 34 N/A N/A 5.8 N/A Cu-Mo 2 C/250 8C [29] 13 40 N/A N/A 5.2 N/A Pd/Al 2 O 3 /260 8C [33] N/A 78 N/A N/A N/A N/A Mo/g-Al 2 O 3 /600 8C [34] 34.297 N/A N/A 32.1 N/A…”

Recent Developments in the Modelling of Heterogeneous Catalysts for CO2 Conversion to Chemicals

“…Noble metal catalysts, mainly Pt and Rh based supported catalysts, have high activity towards hydrogen dissociation, relatively moderate strength with the adsorption of reaction intermediates and the incompletely filled D‐orbital electrons make them easier for the adsorption of reactants with moderate strength, which is further benefiting to form the intermediate “active compound” in RWGS reaction . Besides mentioned catalysts other metal catalysts as active components or as supports are Pd, Ni, Co, Fe, Fe supported on CNTs and carbide (Mo 2 C) catalyst …”

Hydrogenation of Carbon Dioxide to Value-Added Chemicals by Heterogeneous Catalysis and Plasma Catalysis

“…Therefore, the improvement of the catalytic activity for the RWGS reaction can be ascribed to the change of catalyst structure and oxygen vacancies. Except for the above monometallic catalysts, some bimetallic catalysts-i.e., Pt-Co, Fe-Mo and Ni-Mo [25][26][27]-were also prepared and tested in the RWGS reaction. In general, the preparation method of bimetallic catalysts generally can be divided into two categories: (1) the bi-metal was first prepared and then supported on the carrier [25]; (2) the bi-metal as formed in the preparation progress [26,27].…”

“…Ambient pressure X-ray photoelectron spectroscopy (AP-XPS) and environmental transmission electron microscopy (ETEM) showed that Pt migrates on the catalyst surface, and Pt aids the reduction of Co to its metallic state under appropriate reaction conditions confirmed by near edge X-ray absorption fine structure (NEXAFS) spectroscopy [25]. [27]. Similarly, they also found that Fe-Mo/Al 2 O 3 catalyst synthesized by the impregnation method is an efficient catalyst with high CO yield, almost no by-products and relatively stable (60 h) for the RWGS reaction.…”